The present invention relates generally to communications systems, and more particularly, to a vector division multiple access communications system.
Conventional multiple access communications systems include frequency division multiple access (FDMA) communications systems, time division multiple access (TDMA) communications systems, and coded division multiple access (CDMA) communications systems. The frequency division multiple access communications system is based on a unique frequency alignment. The time division multiple access communications system is based on unique time slot assignments. The coded division multiple access communications system is a based on a unique alignment of the coded sequence of data bits used for the modulation.
The present invention utilizes and expands on a modulation systems and techniques disclosed in U.S. Pat. No. 5,237,292 entitled "Quadrature Amplitude Modulation System with Compensation for Transmission System Characteristics", issued to Chethik and U.S. Pat. No. 5,463,355 entitled "Wideband Vector Modulator Which Combines Outputs of a Plurality of QPSK Modulators ", issued to Halloran, both of which are assigned to the assignee of the present invention. These patents disclose systems that utilize vector modulation to implement bandwidth efficiency schemes.
Accordingly, it is an objective of the present invention to use vector modulation to provide for a vector division multiple access communications system.